1. Field of the Invention
The present invention relates to a cool air stream generating apparatus which assures that a large quantity of warm air can quickly be cooled without any necessity for carrying out heat exchanging between a coolant and a so-called cooling unit substantially composed of an evaporator and a condenser.
2. Description of the Related art
As is well known, to cool warm air and then deliver the air having a reduced temperature to a room or a chamber to be cooled, an air conditioner has been hitherto usually used to serve as a cooling unit.
To construct a cooling unit more simply for the purpose of fabricating it at an inexpensive cost and operating it at a low running cost, various proposals have been hitherto made for providing an inexpensive cooling unit. One of the proposals is such that a cloth having air permeability is extensively suspended in front of a blower at a right angle relative to the direction of air blowing and cold water is continuously fed to the cloth so as to allow it to be always wetted with the cold water. As the air delivered from the blower permeates through the wetted cloth, it is cooled by the cold water. Another proposal is such that a water curtain composed of a large number of water droplets is suspended in place of the foregoing cloth always wetted with cold water.
Generally, a live-stock breeding farm such as a chicken farm, a pig farm, a cow farm or the like as well as a plant growing farm such as a so-called vinyl house or the like have a large volumetric capacity, and moreover, exhibit poor sealability, respectively. Thus, to cool the interior of a house of the foregoing type by operating an air conditioner to reduce the temperature of the same, a large size of expensive air conditioner should be installed in the house, causing it to be operated at a remarkably high running cost.
In the case that the cooling unit is constructed in the form of a wetted cloth suspended in front of a blower, it is not suitably employable for constructing it on a large scale, and moreover, the air cooled by it can be blown only within the range of a short distance.
On the other hand, in the case that the cooling unit is constructed in the form of a water curtain composed of a large number of water droplets, the structural scale of the cooling unit is unavoidably enlarged, resulting in a quantity of energy consumed for operating it being undesirably increased.
In the aforementioned two cases, to cool warm air delivered from the blower, heat exchanging is carried out between the warm air and the cooling water. However, this type of cooling unit exhibits a low cool air generating efficiency in spite of a large quantity of energy and water consumed for operating the cooling unit. Although a part of the cooling water is vaporized to extract heat from the air stream discharged from the cooling unit, the resultant cooling effect is unexpectedly very low compared with that obtainable by heat exchanging between the cooling water and the air stream.
In addition, in the aforementioned two cases, since the temperature of the cooled air stream prepared in that way is considerably elevated, there does arises an occasion that this type cooling unit can not practically be employed depending on an application field thereof. Another problem is that when the cooled air stream collides with an operator, he does not always comfortably feel the collision of the cooled air stream.